Distillation Sequences Synthesis Based On A Code Matrix Method And Its Application

The research on the systematic synthesis of distillation configurations has attracted great attentions for a long time. A complete search space consisting of distillation configurations is necessary for configurations constructing according to a given separation subject with energy-saving as the goal. The matrix method, as a promosing approach for multicomponent distillation sequences developed recently, has an obvious advantage in generating a complete search space of regular-column and subcolumn configurations with algrism.In order to facilitate the selection of the configurations with the requirements of separation, a code matrix-based method was proposed based on the marked matrix method. Since the search mode in the encoding of the initial code matrices and the criterions for excluding infeasible configurations were associated with the characteristics of regular-column and subcolum configurations, the code matrix-based method has wider application. And the more systematic and concise principles for the combination of initial code and configuration screening make distiallation sequences synthesis easier to be achieved with algorism.Furthermore, the principles for grouping the components in feed and classifying the configurations were summarized for further selecting the schemes with separation requirements.The code matrix-based method is then applied to Etylene Glycol purification. Based on the parameter sensitivity analysis, the effects of design and operation varibles, such as therotical plates number, position of feed stage, side withdrawing rate and reflux ratio, on the reboiler heat dudy were determined to abtain the design specifications of an optimal three-column distillation sequence. The scheme with the lowest total reboiler heat duty was identified from the sixteen candidate schemes by Aspen Plus optimization. It was found that the scheme with ethylene glycol as a pure product uses less energy due to the energy consumption is needed for further purification of ethylene glycol in the scheme with ethylene glycol produced as a mixture.